Mechanical ciphering system



A. H. REIBER 2,458,734

MECHANI CAL CIPHERING SYSTEM Jan. 11, 1949.

Filed D90. 8, 1945 2 Sheets-Sheet l in ///////l 78 mm i INVENTOR ALBERTH. REIBER, DECEASED 'EMI'LY Y. REIBER, EXECUTRIX AT ORNEY A. H. REIBERMECHANICAL C IPHERING SYSTEM Jan. H, 1949.

2 Sheets-Sheet 2 Filed Dec. 8, 1943 mvm'o R ALBERT H. REIBER, DECEASEDEMILY Y.YRE IBER. EXECUTRIX ATORNEY Patented Jan. 11, 1949 by Emily Y.Reiber, exeeutrix, Evan'ston, 111., assignor to Teletype Corporation,Chicago, Ill., a

corporation of Delaware Application December 8, 1943, Serial No. 513,874

2 Claims. (01. its-=22) This invention pertains to printing telegraphreceivers and particularly to an apparatus for the reception of secretor confidential telegraph messages.

Signaling systems are desirable for naval, military, and civil purposeswherein it is required that messages be rendered unintelligible topersons unauthorized to receive them. surreptitious interception ofmessages may be accomplished, for example, in the case of the Wirecommunication by tapping signal wires, and in radio communication bymeans of receiving apparatus tuned to the proper frequency.

The primary object of the present invention is the provision of asimple, compact, and eflicient apparatus for rendering messagesunintelligible to unauthorized persons.

Another object of the invention is to provide a system or apparatus forprecluding the unauthorized interception of intelligible messages by 1mechanical operation established in response to the respective controlconditions.

A further object of the invention is to provide a decipheringinstrumentality which is readily adaptable to commercially availableprinting telegraph apparatus.

Specifically, the apparatus according to the present invention isutilized to decipher and record previously enciphered messages whichhave been transmitted from a remote station. In order to enciphermessages according to the present system, the elements of the codecombinations of the original, intelligible message are combined with theelements of code combinations provided by a key tape or other controlmechanism. In such arrangement, opposite conditions (that is, oneelement of the original code combination marking and the correspondingelement of the key code combination spacing) produce a marking signal.Like conditions, however, with both elements marking or both elementsspacing, produce spacing signals. This presumes, of course, that each ofthe elements of the respective code combinations are related to eachother. That is, the No. 1 element of the original code combination iscombined with the No. 1 element of the key code combination, and soforth. To take a specific illustration, let it be assumed thatit isdesired to encipher the character R which in the Baudot code is composedconsecutively of spacing, marking, spacing, marking, and spacingconditions. Let it be further assumed that the key tape with which theparticular enciphering operation is to be performed occupies a positioiiwhereat it is conditioned for produoihg the letter Y combination, whichin the Baudot code is composed consecw tively of I marking, "spacing,marking, spacing, and marking conditions. Under the assumed conditions,the encipherin-g operation would restill, in the PTOCIUEtiOh of an allmarkin or Letters combination, since in this particular illustration oposite conditions or an the related elements of FR and Y codecombinations are provided. This will be 'i'eadil-y apparent rro'm thefollowing chart Whei 'eih the letter M indic'ates 'a marking conditionand the letter S indicates a spacing condition:

Original Signal R S M. s M s KeySignaWY M s M s M M M M M It isunderstood that both the transmitting and receiving end of a telegraphline will be equipped with identical key tapes which during messagetransmission will occupy identical positions. During transmission thekey tapes are advanced between characters to modify the key signal, butboth tapes "occupy the same corre spohding positions at all times. Astation which receives enciphe'red signals is thus enabled to decipherthe unintelligible signals transmitted over the telegraph line bycombining the enciphered signals with key -signals provided by its keytape.

To illustrate a deciphering operation, the exa-inple g'i'veii above inconnection with the en- 'ciphering operation will be continued, and itwill be assumed that a receiving station received the enciphered signal;namely, Letters. The Y combination provided by the key tape at thereceiving station can now be combined with the received Letterscombination to decipher the enciphei'ed signal to thereby reproduce theorig-"- inal signal R," as clearly shown in the followin'g chart:

Ehciphred Signal Letters M M M K- ey'Signal Y. M M Original Signal R" MS S A more complete understanding or the invenmen may be has from therenewing description aken iii conjunction with the accompanyingdrawings, wherein: V

Fig. 1 is a front elevatioh'al view of the re- Fig. 5 is an enlargedfragmental view showing I the essential elements of the decipheringdevice and graph system embodying the present invention.

The deciphering mechanism according to the present invention isillustrated in the figures as applied to a. type wheel printer of thetype shown Fig. 6 is an electrical circuit diagram of a tele- I incopending application SerialNo. 397,193, filed June 9, 1941, by W. J.Zenner. framework is indicated at H and comprises side frames l2 and I3.Mounted on the side frames l2 and I3 are journal brackets l4 and I5which support the main cam shaft l8. Also spanning the frames l2 and|3is a plate ll, which carries a series of five electromagnets Hi, '21},2|, 22, and 23 mounted on a bracket 24 and which constitutes part of thedecipheringmechanism according to the present invention. Journaled inthe side frames l2 and I3 and extending therebetween is a pivot shaft25. Pivotally carried on the pivot shaft 25 substantially midway betweenthe frames l2 and I3 is a printing arm 26 which carries at itsextremity. (the left end as viewed in Fig. 3) a platen member 21.

Platen member 27 cooperates with a type wheel segment 28 fixed to a typewheel shaft 29 journaled in a bearing 38 mounted in a plate 35 whichspans the frames l2 and i3. The type segment 28 is provided with fourrows of type faces; and a shift mechanism therefor is exemplified by aplurality of stop bars 33, provided for controlling the shiftingmovement of the type segment 28 to effect printing from the various rowsof type. The bracket 34 is provided for guiding and supporting the tapebetween the platen 21 and the type segment 28. A spring 35. normallybiases the type or printing arm 26 downwardly to hold the platen, 2'!free from the type segment 28. The printing operation is effectuatedthrough the instrumentality of the vertical link 36 extending from theprinting arm 26 and a printing cam (not shown) carried on the main shaftl6. Carried in brackets 31 (one of which is shown in Figs. 3 and 5)mounted on plate ll is a pivot shaft 39 on which are pivotally carried aseries of selector levers 4| to 45. Each of the levers 4| to 45 isprovided witha cam follower projection 46 which cooperates with theperiphery of an associated selector cam 41. There are five such cams 41,one associated with each of the five selector levers 4| to 45. The cams4'! are of similar cam contour but are displaced on the shaft l6angularly so that the cam notches 48 are disposed in a helicallyarranged series whereby coaction with the cam followers 46 will occur ina sequential manner as the series of cams 41 rotates in synchronism withthe speed of code impulsing. The levers 4| to 45 are normally biased ina clockwise direction about the pivot shaft 39 by individual springs 49.

The extremities 52 of the levers 4| to 45 cooperate with a shoulder 53of an associated selector bar 54. Bars 54 are positioned vertically inthe printer mechanism and are mounted on a shaft 55. Each of thebars'54' is provided with a slotted hole 55 cooperating with the shaft55 so The printer;

that an individual spring 51 associated with each of the bars 54 tendsto hold the bar 54 in its vertical position against the bottom of theslot 56. The vertical bars 54 are provided with a series of notches onone edge thereof and cooperate with a plurality of function bars 58 inthe manner described in the copending Zenner application.

J uxtapositioned to each of the selector levers 4| and 45 is a companionbar 59 which is slidably mounted with respect to its associated lever 4|to v 45 on pivot shaft 39 and a stud 6| fixed to said associated lever.Each of the companion bars 59 is provided at its left-hand extremity (asviewed in Fig. 3) with a vertically projecting portion H, and at itsright end with a horizontally extending portion 12. Each of the bars 59is normally. biased rightwardly (as viewed in Fig. 3) by a spring 73individual thereto, which extends between depending lugs on bar 59 andits associated levers 4| to 45. I

Extremities 72 of each of the bars 59 cooperate with the armature 14 ofeach of the deciphering magnets l9 to 23. Armatures 14, when seized bytheir respective magnets l9 to 23, extend their individual springs 15',and thus permit springs 13 to urge or bias'their respective bars 59 tothe rightward position, as shown in Fig. 3. When the magnets l9 to 23are de-energized, their individual springs 15 rotate the armatures 14 totheir clockwise position, as shown in Fig. 5. Springs 15 are strongerthan the springs 13, so that when the magnets I9 to 23 are de-enegized,the springs 15, through armatures 14, will urge the bars 59 leftwardlyagainst the action of biasing springs 13.

The vertically extending portions H of the bars 59 cooperate with thearmature 16 of electromagnet TI. The magnet H is the single 'line magnetof the receiving selector mechanism and responds successively to thecode signal impulses. The line magnet 11 is suitably mounted on abracket l8. The armature 16 of magnet TI is pivoted at 19, and a spring8| normally tends to rotate the armature 16 in a clockwise directionabout the pivot l9 when the magnet 11 is deenergized. An adjustable stopscrew 82 is provided to limit the clockwise movement of the armature 15so as to correspond to the leftward movement of the bars 59 by thearmatures 14. As shown in Fig. l, the lower extremity of armature l6spans all of the projections l I.

As illustrated in Fig. 2, the cams 4! are carried on a sleeve 83 whichis drivingly connected to shaft l6 by means of a friction clutch. Shaftl6 derives its power from a motor 84 through a pinion 85 and a gear 86.The cam assembly on shaft l5 also includes a cam 81 which acts upon abell crank lever 88 to cause an extension 89 thereof to act upon all ofthe bars 54 to return them leftwardly to their normal unlatched position(as shown in Fig. 3), thus disengaging those members 54 which areengagedby the end 52 as will presently be described, and permitting them to bereturned by their springs 51 to their upward normal position, with theshaft 55 at the bottom of the slot 56.

General operation In the operation of the apparatus according to thepresent invention, it is assumed'that the normal stop current on theline 9| (Fig. 6) is marking, in which condition the armature 16 will beseized, and the cam sleeve 83 on shaft IE will be blocked againstmovement in Well-known manner in start-stop operation. The electrobesensed by a record reader or tape sensing device to control thetransmission of code combinations of signal impulses to the electromanets l9to 23. Upon receipt of the start impulse, which in the presentillustration is a no-current impulse, the magnet 11 will betie-energized, thus releasing armaturefldwhich responds to the pull ofthe spring 8|. This action initiates the rotation of the sleeve 83 inwell-known manner. The cams .41'wi11 then sequentially allow theleversjil to 4 5 to respond to the pull of their respective springs 49unless said levers are fblocked through the coaction of portions 1! andarmature 15. For example, assuming that the lever 43 (through projection1|) is not blocked, :its cam follower portion 46 will fall into thedepression in its respective cam 41 and lever 43 will be caused torotate slightly in a clockwise "direction. That is, if the lug 1a is notobstructed by'the armature 16 when the portion 46 of lever 43 engages acam notch 48, the lever 43 will be free to rotate clockwise to bring theend 52 there- ;of out of the path of shoulder 53 of lever 54 to permitthe spring 51 thereof to rotate said lever '54 to bring the shoulder 53under the extremity 52. Then, when the cam 41 rotates further to causeitshigh portion to urge the lever 43 counterclockwise, the bar 54 willbe depressed against the action of its spring 51.

" 'Unde'r'certain conditions of operation, in response to predeterminedcode signals, certain 'ofthe bars 54 will function to operate certain ofthe stop bars 33 to control the shift movement of the type 'wheel 28 tocause printing in a selected one of the four rows of type. This specificmechanism is fully described in said copending Zenner application.

Of course, if the projections 1| are blocked by the armature 16 noclockwise rotation of levers 4| to 45 will occur and, hence, the bars 54associated therewith will not be operated downwardly. As previouslydescribed, cam 81 will act through ball 89 to disengage the operatedbars 54 from the extremities 52 of the levers 4| to 45 with which theyhave'become engaged,

whereupon the respective bars 54 will be raised by their springs 51 tothe position shown in 'Fig. 3.

" In the operation of the deciphering arrangement according to thepresent invention, the levers 4| to 45 are controlled jointly by theselector electromagnet 11 and by the deciphering electromagnets |9 to23. Having reference to Figs.3 and 5, when the signal impulse receivedby the selector magnet 11 is of a marking nature, the magnet 11 will beenergized and the armature 15 will be attracted, or moved to itsposition shown in Fig. 3, to bring its lower extremity into a positionto cooperate with the lug 1| (of any one of the bars 59) when the bar 59is in its rightward position. Under normal conditions of operation whenthe printer mechanism is employed for recording intelligible messages,the levers 4| to 45 are controlled solely by the selector magnet 11, sothat clockwise rotation of the levers 4| to 45 sequentially under thecon- W trol of cam 41 is controlled by the armature 16 such that "whenthe armature 16 in its attracted position obstructs the projection 1|the cam follower 46 of levers 4| to 45 associated therewith will notfall into the notch 48 of the cam 41.

,igvhen the armaturelfi isout of. the path ofthe ,projectien 1| the.levers M .to 45 will respond to the pull' of. their springs 1.49 andclockwise rotation will resnltto blf i the extremity 52 of a 1ever.4|fto45 abovthe shoulder 53' of its associated bail-i4, and" inengagement therewith 'so that subsequent rotation of cam 41 will depressthe arm 54 engaged with the levers 4| 11045.

,However, under thecontrol of the deciphering arrangement according tothe present invention, .the movement of levers 4| to 45 will be furthergoverned by the deciphering device, ex-

emplified by magnets l9 to 23, inclusive. In the position illustrated inFig. 3, the deciphering .magnet 2| is shown energized under thecontrolof the-ke'y'tape 92, in which condition the armature 14 isattracted, whereupon the bar 59 isactuated by spring 13 to its rightwardposition'to bring the vertically extending portion 1| 43 in Fig.3),through projection 1|, will be blocked against operation under controlof cams 41.

Having reference to Fig. 5, the four difierent conditions of operationsunder the joint control of .the deciphering magnets I9 to 23 and theselector magnet 11 will be described. The con- .ditioniof operationshown in Fig. 3 is exemplified in Fig. 5 with the armatures 16 and 14 intheir dotted line positions. Under this condition of operation the lever43 will not be permitted to rotate clockwise and hence its correspondingbar 54 will not be operated.

According to a second condition of operation let it be assumed that themagnet 11 is energized by a marking impulse and that the decipheringmargnet 2| is de-energized, so that armature 16 assumes its dotted lineposition and armature 14 assumes its solid line position in Fig. 5. Dueto this control, the bar 59 is actuated to its leftward position byreason of the fact that the spring 15 preponderates the weaker spring13. Thus, the vertical projection 1| is moved out of vertical alignmentwith the armature 16 so that upon rotation of cam 41 the lever 43associated .tremity 52 will be elevated to permit the shoulder 53 of bar54 to be introduced therebeneath so that when the high portion of thecam 41 actuates the lever 43 counterclockwise, the bar 54 will be urgeddownwardly.

Under a third condition of operation, it is assumed that the decipheringmagnet 2| is deenergized, and that the bar 59 is maintained in itsleftwise position by the stronger spring 15; and further that theselector magnet 11 has heen de-energized in response to a spacingsignal, whereupon armature 16 is rotated clockwise (to'its solid lineposition) by its spring 8| into engagement with stop 82 to bring thelower extremityof armature 16 into the path of the vertical portion 1|.Thus, when cam 41 rotates, the cam follower projection 46 is preventedfrom falling into the notch 48- of the cam 41 due to said engagement ofportion 1| with armature 16. Hence, it is seen that when any of thedeciphering magnets 2| to 25 is conditioned in response to a spacingsignal and the line magnet 11 is similarly conditioned, the resultantcondition is a spacing condition; that is, levers M to 45 (lever 43 inthis particular instance) are not operated in response to the rotationof cam 41.

Under a fourth condition of operation, the deciphering magnet 21 isenergized, thus causin the armature I l to be attracted to the dottedline position shown in Fig. 5, and thereby permitting the spring 13 toactuate the bar 59 to its rightward position bringing the verticalportion II to the dotted line position. Also, under this condition ofoperation the selector magnet I7 is de-en-ergized in response to aspacing signal and armature I6 will assume the solidline position shownin Fig. 5. It will be observed, then, that the projection II is notblocked by the armature 76 since the armature is in the solid lineposition and the lug IE is in the dotted line position in Fig.Therefore, upon rotation of cam in, the cam follower projection 46 willfall int-o the notch 48, thus imparting clockwise rotation to lever 43(since projection H is not obstructed). Accordingly, the extremity 52will be brought above the shoulder 53 and lever 54 will be biasedinwardly by its spring 51 so that bar 54 will thereafter be operatedunder the control of cam 41.

With the. mechanism just described it is seen thatwhen the selectormagnet 11 and deciphering magnet 2| (or any one of the decipheringmagnets I9 to 23) assume the same conditions, namely, both marking 01'bothspacing, the lever 43 operates as. it would in response to a spacinsignal if it were solely under the control of the selector magnet "I7.On the other hand, if the selector magnet 71 and deciphering magnet ZIare operated in opposite manner, the lever 43 responds as it would for amarking signal if it were solely under the control of the selectormagnet l'I, which condition conforms to the tables presentedhereinbefore.

Electrical circuit In Fig. 6 is shown an electrical circuit or diagramof a system embodying the receiver according to the present invention.In the rectangl-e ml is shown a set of transmitting contacts I02 such asare associated with a rotary cam distributor (or other type ofdistributor), and a series of contacts 103 which are controlled, in thepresent embodiment of the invention, by a key tape IM. It is, of course,understood that any other form of control mechanism for operating thecontacts IE3 is contemplated. It is noted that each of the contacts I03is connected to a solenoid I05, and that the contacts I02 were includedin a circuit extending from ground, through battery, then through thecontacts I02 sequentially, over the line conductor 9|, and through thewinding of the selector magnet TI to ground. Such a transmitter isdisclosed in copending application Serial No. 496,552, filed July 29,1943, by A. H. Reiber.

The magnet H is shown as included in a receiving station indicated bythe rectangle I05, and the armature T6 and bars 59 are showndiagrammatically. Also shown associated with the bars 59 are thedeciphering electromagnets IS to 23, inclusive. Magnets I9 to23 areincluded in a circuit extending from a common ground Wire to theirrespective contacts I07 governed by tape controlled levers I08, thenceto grounded battery. It is understood that control mechanisms other thansuch as are controlled by tape may be employed in carrying out thepresent invention. The stepping of the tape is, of course, presumed tobe effected cyclically in phase with the transmission and reception ofcode signals.

As previously mentioned, identical key tapes I04 and 92 (or identicalcontrol mechanisms of any other type) are provided at the transmittingand receiving stations IDI and I06, respectively. It is understood thatthese control mechanisms are placed in their respective station units inidentical positions so that in the operation of the machine thetransmitting apparatus contacts I02 and the selector magnet 'I'I shallhave their selective operations altered in a uniform manner.

Although a specific embodiment of the invention has been disclosed, itis understood that the invention is not to be restricted to thestructure herein described but is to be given an interpretationdetermined by the scope of the appended claims.

What is claimed is:

1. In a recorder, cam means, a plurality of instrumentalities carried ona common pivot and adapt-ed to be operated in a predetermined manner bysaid cam means, signal controlled means, deciphering means, acorresponding plurality of elements carried on said pivot and duallycontrolled by said signal controlled means and said deciphering meansforexercising control over said instrumentalities, each of said elementsbeing slidably articulated to and in juxtaposition with an associatedinstrumentality, and selectable members operated by saidinstrumentalities according to the control exercised by said elements.

2. In combination, a selector including a plurality of cams, a followerassociated with and urged into engagement with each of said cams, saidcams having low portions for receiving the cam followers followed byraised portions for actuating the followers invariably, a pivot forsupporting said followers, signal responsive means normally operableselectively to block the followers from engagement with the low portionsof their cams, deciphering means, a correspond ing plurality of elementscarried on said pivot and dually controlled by said signal responsivemeans and said deciphering means for exercising control over saidfollowers, each of said elements being slidably articulated to and injuxtaposition with an associated follower, and a slidable actuatorassociated with each follower for actuation thereby, said actuatorsoperated by said followers according to the control exercised by saidelements.

. EMILY Y. REIBER, Emecutria: Under the Last Will and Testament ofAlbert H. Reiber, Deceased. 1

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Hagelin Feb. 12, 1946

